Electrically-driven coal pulverizer and fire feeder



P. L. CROWE Oct. 29, 1929.

ELECTRIGALLY DRIVEN COAL PULVERIZER AND FIRE FEEDER Filed Aug. 13, 192

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I N V EN TOR, Eu? 1;. 6902MB.

ATTORNEY.

Patented Oct. 29, 1929 um' rao STATES mm L. CROWE, or BALTIMORE, mAnYIJANn ELECTRICALLY-DRIVEN cormwwmzmmn immune f 1 A Application "filed au ust 13, 192 7. isemi no; 212,668.

This invention relates to pulverizers, and especially to an improved ;electrically'driven coal pulverizer and fire feeder. a

The main object of this invention is to 5 combine in a compact, exceedingly simple and thoroughly practical unitary structure, all the essential members for containinglump coal, pulverizing the same, thoroughly mixing the pulverized coal with an air current, produc- 10 ing the necessary air current for keeping the pulverized coal in suspensiomcarrying this current of air and suspended pulverized coal into a furnace or the like,and at the same time using the force of gravity in cooperation with the said air current forconveying the pulverized coal and air through the machine." Y

A further object is to combine, within a single casing and on a single' verticalshaft, a pulverizing member, an air current producing member, and a p'ower-generating member, all in such relation that the pulverized coal can pass down from the top to the bottom of said casing, through said power-generating member while the latter operates to generate the ower for driving the shaft and the mem ers carried thereby. f

A further object of the'invention istoprovide a machine of this character whose vertical shaft rotates on "roller bearings, and

to utilize the air current producer to shelter the roller bearings from the descending pulverized coal. 7 I w A further object is to provide a machine of this character whose vertical shaft is hollow from end to end so "the shaft can be utilized as an oil-duct for applyingoil or other lubricant to the bearings in the' bottom of the casin.

A lrther object is to provide amachine of this kind with air inlets and with closures to regulate the capacity ofthe air inlets.

Other objects and importantfeatures are pointed out or implied in the following' details of description in connection with accompanying drawings in which: I, I

Fig. 1 is a vertical sectional view through one form of'machine constructedin accordg ance with this invention. a r i Fig. 2 is a similar view of a difierentform 5o of the same invention, a partof the outlet portion being broken oii',- the rotorof the electric motorals'o being omitted. W 7

7 Fig.3 is a 'sectional view jalongthe line a;3 ofFig; 2.; I I

,Fig. 4 is a planiview ofthe fanused in both 56 forms of theinventiomthis view also showing a he vertical hollow shaft ,in horizontalfsectioni 1 Figure 5 is a vertical detail sectional view showing a modified form in which the spokes 0r webs of .the rotor constitute fan blades, so the rotor serves the dual purpose of generat-r ing power and creating a draftof air through thepowerjgenerator; v it M j r V j Referring to these drawings detail, in which similar, reference'cliaracters 'corre- 'spond to similar parts in the several Views; 'butfirst referring 'particularly to Figuresl and the casing is shown composed of three W separately formed sections fitted together in s 'superposed relation secured in place by 1 any appropriate means (not shown) that is,

a base section 5, an intermediate section 6,

and an upper section 7 thelatter forming a hopper in which is contained an annular stationaryabrading member 8 of any appro priate material "and formed with an annular series of air-passages or air inlets 9. The

periphery of the'member 8 fits snugly in the hopper 7; but the bottomfthereof is spaced b from the bottom of the hopperto provide an,

air chamber in-which the air from'the passages 9commingles with the pulverizedrcoal that passesdown between the conical hollow of the member 8 and arotary abrading member 10 'whichlhas a conicalo'r downwardly taperingflowerjend which is only slightly I spaced" rom the inner wall of the abrading memberSQ r Y a y A hollow vertical'shaft 11 carries there--96 tary abrading member 10, this shaft having its lower end provided with a conical member a I 12 which is rotatably supported by conical bearing members 13 ina bearing-seatl i, such bearing-seat being formed or secured in the '95 bottom of the base member 5. A ball bearing} seat 15 is formed'or secured on the'hopper a member 7 and coo eratesfwith a bearing collar" 16 to format rust bearing to prevent the :ztbrading member 10 frombeing raised by "109' I I I action of the coalbeing pulverized. In this connection, it should be understood that the members 10 and 16 are adjustably secured to the shaft 11 by means of set screws 17, and that similar set screws are employed for securing a rotor 18and a fan 19 on the shaft 10. V Referringagain to the .rnto r18,,iffi should be understood thattthis is the rotary element of an elec'tric motor which drives the abrading member 10 and fan 19, through the medium of the shaft 11, and that it is substantially of the same form as the oneshown in Figure 3, that is, having broad flat spokes or webs 20 connecting its annular outer portion to its hub, and provided with through openings 21 which constitute :passages through which air and suspended particles of coal are drawn zdownwardfby the force" of gravity and the fan 19. Thestator ,Of the motoris shown at 22, this ,being' secured to the annular wall 23..of the ,basemember .5 by any appr priate m ans, suitab e insul ting material being provided at 2d so as to insulatethe stat r from thewalll23: Acommutator or collecting :ring'25 ismoimted Qnand suitably insulated from .thetop of the, rotor 18, and :any suitable form -of .brush'tnot own; may be mounted at any suitable place and in any suitableway. 'llhisflcom nuta tor is hollow so the :air and pulverized coal can pass therethroughr This cmotor is shown somewhat conventionally, and its winding 26 maybe of any appropriate type, ,itbeing understood that fthisis an A. G. motor, but that a D. G. motor or other power may be substituted therefor; according 'to the conditions under which this machine is to be operated. a i g i I The base .5is preferably of substantially convolute form or outline, and the shaft v11 is mounted .eccentrically therein, as shown in Figure 3,. thus providinganoutwardly di' verging air passage?! which terminates in an outletor discharge opening 28 which is intended to be directly or indirectly connected to a furnace or the like for ,feedingpulverized coal and air for combustion. I

The fan 19 is preferably of the form shown in Figure 4e, and includes a lower disk 28, arcuate blades 30, and one or more hubs 81 secured to ,the shaft- 11. Spokes .32 may also be provided, although they are not-strictly essential, for the blades ,30 are rigidly united with the disk 29. The upper part ofthe inn is open,:.as shown in Figured, so the air and suspended coal particles can move downward thereinto, but the disk :29, being imperfonate,

and also beingflconcaved at its under side,

eifectuallyfshields@thelconioal bearings against 'the entrance of the pulverized" coal into the bearing seat 14. A fan can .a lso be located in th nte ior of the l oton, as shown in :F gure flhisview 'showsthe spokes or webs -20? incl ned in such-direction thatwhen theshaft '1] :is .turned c oekwise, these, webseer 7 stitute fan blades which draw the air downward through the combined fan and generating element shown in this Figure 5.

35 and 6 andis adapted to be slidup for closing or partly closing the openings 34;, thereby regulating the 311101111b-0f13i1 fed'lnto'tlle machine; Vertical guidesor bars 36 and .37

means, and theclosure member or cylinder 35 may be guided thereby while being raised or lowered. Any appropriate imcans {not shown) may be provided to hold the-cylinder 35 in its different verticaladjustments. 1 The hopper is perforated .or foraminated at 381:0 permit the mixture of pulverizedcoal and air'to pass therethrough under the force of gravity and the urge or suction produced by the fan 19. r

The'operation is as follows: Assuming the shaft 11 -to be carryingthe united parts in the clockwise direction-indicated by, thearrow. above Fig. 4, it isevident' that theinnerends of the blades 30 will be cutting the internal volume of air and forcing it outward in the direction of the arrow on the disk 29, therebyriten d-ing .to

creates Vacuum in the space surrounded by the blades 30, and thusdrawing the mixture of air and-ccal-dust @down into th "fan, then discharging it into the outwardly converging channel 27 and through the furnaceefeejding 'outlet'28. V p

The-form-shown in Fig.3 illustrates how the invention can be utilized inconnec'tion with'shoes 22 provided with-wi-ndin-gs22 of connecting wire, so as to com%bine with a rotor such as shown in Fig, 3;) to form-a D. Q. motor fOl' driving the shaft -ll-and therebyidriving the fan 19 and'abrading me1nher or wheellO which may be of carboruin dum or Qt'heISl1lt?bdB ,mater-ial;- In this form of ;tl1ie-inuention, the wall of "the hopper 7* is formed integrally with the base member 5 but the bottom 7 10f the hopper 51s separately formed, provided with retaining ribs 7 to prevent the lumps ofcoal from sliding while being abraded, and-seatedion :ashoulder 7 where it i'ssedured by any; appropriate means; (not shown) This disk, orghopperbottom 7 is provided rwithiperforations .or foraminations 38 to permitthesair to carry the pulverized-recal therethrcughui cense:

maybe secured in place'by any appropriate quence of the fan 19 and the force of gravity.

The cylindrical part 6 of the casing is provided with air inlet openings 36, oneof which is shown, and the other omitted with the missing section of this form of the invention. The openings 34* are provided with doors 35*, each having hinges 36 and latches 37, so they can be opened or partly opened for regulating the quantity of air to be passed through the machine.

Although I have described these embodiments of my invention specifically, I do not intend to limit my patent protection to the v said hopper and carried by said shaft; and a fan on the lower end of said shaft and rotatable therewith; said motor having passages therethrough and being effective to turn said shaft together with said pulv'erizing member and fan; said fan being effective to create an air draft downward through said casing and thereby discharge the air and the pulverized material from said casing.

2. In a device of the character described, the combination of a casing which includes a hopper, air inlets, and an air outlet at its lower end, said lower end having a bearingseat therein, said hopper having an annular abrading member non-rotatably mounted therein; a shaft mounted vertically for r0- tation in said casing and provided with roller bearings in said bearing-seat; a disk mounted on said shaft immediately above said bearing-seatand adapted to shelter the latter; fan blades united with said disk and extending upward therefrom and being spaced from one another so as to discharge air and pulverized material between them; an abrading member on the upper end of said shaft and extending into said annular member and being rotatable withsaid shaft for pulverizing coal or the like, and a motor in'said casing and operable to turn said shaft and thereby rotate said abrading member and fan.

3. In a device of the character described, the combination of a casing which includes a substantially convolute base provided with a fan and with an outwardly diverging air passage which terminates in an outlet open ing, said casin including acyhndrical part extending up rom said convolute base, and also including a hopper at its 'upper end, the casing also being provided with air inlets adjacent to the lowertend of said hopper; a

shaft extendingvertically through the center of said cylindrical part and hopper and carrying said fan; an abrading member in said hopper and carried by said shaft; and a cured on said shaftand operable to rotate the latter so as to rotate said abrading member and said fan, substantially ,asdescribed, for the purposesspecified. I

4. In a device of the character described, the combination of a casing provided with a hopper, air inlets at the lower part of the hopper, a bearing-seat in its lower end, and an outlet opening horizontally disposed from said'bearing-seat; a fan carried thereby, a vertically disposed shaft, rotatably mounted in said bearing-seat; a motor above said fan v and having its rotor mounted on said shaft while its stator is secured to said casing; an

abrading member carried by said shaft in said hopper; and means for regulating the capacity of said air inlets, substantially as shown.

5. In a device of the character described,

the combination of a casing including a hopper, air inlets at the lower part of thehopper,

and an air outletat the lower part ofthe casing; a shaft mounted vertically for rota tion in said casing; a fanon said shaft and rotatable therewith in the lower part of the casing; a pulverizing member on said shaft in said hopper; a motor in said casingand having its rotor on said shaft and adapted] to rotate the latter and thereby rotate said fan and pulverizing member, said rotor being provided with openings therethrough;

and a funnel which shelters said stator and the periphery ofsaid rotor and directs air and pulverized material throu h said rotor under the urge of said fan, substantially as shown and specified.

6. In a machine of the character described,

the combination of a casing'including a hopper at it upper end, an outlet opening at its lower end, and air inlet openings at the lower end of the hopper; a shaft mounted vertically for rotation in said casing; a motor in said casing and having its rotor secured .on said shaft; a rotary pulverized member in said a hopper and carried by saidshaft; and a fan on said shaft and rotatable therewith; said I motor being between said pulverizing member and fan and having passages there'- through and being effective to turn said shaft together with said pulverizing member and fan; said fan being effective to createan air draft downward through said casing and thereby discharge the air and the pulverized material from said casing.

In testimony whereof I afiix my signature.

' PAUL CROWE.

70 motor having its stator secured 1n the cyhnvdrical part of said casing, and its rotor se- 

